<%@ page contentType="text/html; charset=utf-8" language="java" pageEncoding="utf-8" %>
<%@ page import="java.sql.*, org.json.simple.*" %>
<%@ include file="/common.jsp" %>
<%
	//set Chinese Char 
	//request.setCharacterEncoding("utf-8");
	//response.setCharacterEncoding("utf-8");
	//response.setContentType("text/html; charset=utf-8");
	
	//set the content don't use cache
	//这样可以避免客户端 发送ajax请求，可能使用的是缓存数据，导致数据无效
	response.setHeader("pragma","no-cache"); 
	response.setHeader("cache-control","no-cache"); 
	response.setDateHeader("expires", -10);

	/*session*/
	out.clear();	//这样在客户端就不会出现N多空行开头了
	//JSONObject json = null;
	session.removeAttribute("user");
	session.invalidate();
	out.print(true);
	out.flush();
	
%>